Ratchet winch

ABSTRACT

The present invention relates to hoists, winches, and the like, and more particularly, to such apparatus which utilize ratcheting means to take in and let out cable. The apparatus of the present invention uses reciprocating dual pawls and an eccentrically mounted linkage arrangement to engage and disengage the dual pawls. Cam surfaces are also utilized to engage one or both of the pawls when the linkage is in its disengaged position while tension is still being exerted through the cable, or in an alternate embodiment, when no tension is exerted through the cable. A disc brake is also utilized to vary the braking force supplied to the ratchet wheel.

United States Patent Walter L. Blackburn 6105 England St., Houston, Tex.77021 [21] Appl. No. 722,658

]22] Filed Apr. 19, 1968 [45] Patented June 1,1971

[72] Inventor [54] RATCHET WINCH 25 Claims, 20 Drawing Figs.

so 2a F 44 46 4a 1,585,118 5/1926 Schoolfield 254/186H.C. 2,302,9312/1967 Blackburn 1. 254/186 Primary Examiner-Harvey C. I-IornsbyAttorneys-James F. Weiler, Jefferson D. Giller, William A.

Stout, Paul L. DeVerter 11, Dudley R. Dobie, Jr. and Henry W. HopeABSTRACT: The present invention relates to hoists, winches, and thelike, and more particularly, to such apparatus which utilize ratchetingmeans to take in and let out cable. The apparatus of the presentinvention uses reciprocating dual pawls and an eccentrically mountedlinkage arrangement to engage and disengage the dual pawls. Cam surfacesare also utilized to engage one or both of the pawls when the linkage isin its disengaged position while tension is still being exerted throughthe cable, or in an alternate embodiment, when no tension is exertedthrough the cable. A disc brake is also utilized to vary the brakingforce supplied to the ratchet wheel.

PATENTEDJUN 1M 3.581.586

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RATCHET WINCH BACKGROUND OF THE INVENTION The present invention isdirected to actuating and braking means for ratcheting devices such asthe ratchet winches used to make up a barge train by cable and hoistssuch as chain blocks or chain falls.

Discussing first the ratchet winches, it was common in the prior art tomake up barge tows by the use of steamboat ratchets, or various types ofmanually or power-operated cable winches. The use of such devices haverequired extensive labor or expensive power means and considerable time,especially when used to make up long tows comprising to 30 barges whichare now quite common. An improved manually operated ratchet winch foruse in making up such a barge train is disclosed in my US. Pat. No.3,302,931, issued Feb. 7, I967. The winch disclosed therein provides aquick and mechanically efficient tow cable tightening means, whichsubstantially decreased the time and labor necessary when connecting anddisconnecting barges.

One problem in this area is that of providing actuating means for such awinch which can effectively ratchet the cable into the winch with aminimum of force required, and still provide means whereby the cable maybe gradually let out of the winch. Many prior art devices could only becompletely released, allowing the tension in the cable to unwind it.This, of course, was undesirable due to the fact that the letting out ofthe cable from the winch could not be controlled as desired. The rapidunwinding could be dangerous to personnel and equipment and oftenresulted in a backlash in the cable.

In the field of chain, wheelor lever-actuated hoists, the problem isalso present of providing efficient actuating means that will functiondependably and with a minimum amount of effort. When an object is beinghoisted, it cannot be released in a freewheeling manner. Thus, it isalso necessary to provide means to slowly lower or back off theobject.-lt is also desirable to be able to lift with the hoist todesired levels with a high degree of accuracy, and to provide suitablebraking means to maintain the object lifted at desired heights.

SUMMARY OF THE INVENTION The present invention provides an improvedactuating means for use in combination with a ratchet winch, such asdisclosed in my above-cited patent, as well as with other winches, chainhoists and the like. The present invention further discloses a brakemeans which may also be used with such actuating means to provideadditional control over the holding and unwinding of thecable.

As applied to the winch, the present invention utilizes reciprocatingdual pawls for actuating the ratchet wheel to take in the connectingcable. The pawls are connected to a linkage arrangement by two leafsprings, one spring being connected to each pawl. A control lever isalso connected to the linkage arrangement by means of a control shaft,the lever being rotatable to first and second positions. In one of thepositions, the linkage arrangement insures the connection between thepawls and the ratchet wheel, whereas in the second position the linkagedisplaces the pawls, normally moving them away from contact with theratchet wheel.

One embodiment of the present invention, however, utilizes a cam surfaceadjacent one of the pawls, which surface directs this adjacent pawl tothe ratchet wheel when the operating handle moves this particular pawltoward the ratchet wheel. This is sufficient to bring about contactbetween the pawl and the ratchet wheel when the control lever is in itssecond or disengaged position. So long as there is sufficient tension onthe cable, this adjacent pawl will remain engaged with the wheel. Thepawl that was directed by the cam into contact with the ratchet wheelwill, in turn, act as a cam surface for directing the nonadjacent pawlto, and engaging it with, the wheel. In this manner, the pawls arealternately moved to the ratchet wheel for engagement.

Another embodiment utilizes a cam surface adjacent each pawl, whereby atleast one pawl will be in continuous contact with the ratchet wheel.This will insure against freewheeling escape should the tension bereleased long enough to free the pawls. Although either embodiment maybe used with winches or hoists, this latter embodiment is preferable toprevent a sudden drop of the object being lifted. Furthermore, thepresent invention is susceptible to use with lever, wheel or mechanizedapparatus. In addition, various brake means are utilized which canrelieve some of the force exerted on the dual pawls during the lettingout, and act as a supplementing retarding force against the tension inthe cable.

It is, therefore, an object of the present invention to provide improvedratcheting devices.

A further object of the present invention is to provide improvedactuating means for such ratcheting devices, which means are reliableand which provide for ease of operation, manufacture and assembly. 7

A still further object of the present invention is to provide means tobe utilized with a dual pawl-actuating means to expeditiously engage anddisengage the pawls while taking in or letting out cable, so long astension remains in the cable.

An additional object of the present invention is to utilize linkagemeans having an engaged and a disengaged position, and a cam surface forcooperating with one of the pawls to insure their engagement with theratchet wheel when the linkage means is in its disengaged position, solong as tension remains in the cable.

Another object is to provide cam surfaces for both pawls to insurecontinuous contact with at least one pawl and the ratchet wheelregardless of whether tension remains in the wheel or not. This insuresagainst accidental release or letting out of the cable.

A further object of the invention is to provide brake means to act as aconstant or variable retarding force against the ratchet wheel toprevent undesired free release of the cable.

Other and further objects, features and advantages will be apparent froman examination of the following description of a presently preferredembodiment of this invention, which is given for the purpose ofdisclosure, when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Like character references designatelike parts throughout the several views of the drawings, which views areas follows:

FIG. 1 is an elevation view of one embodiment of the ratchet winch onwhich'the present invention may be utilized.

FIG. 2 is an elevation view, partially in section, showing the actuatingmechanism of the present invention with the control lever in its engagedposition and the operating handle moving in a counterclockwisedirection,

FIG. 3 is an elevation view of the apparatus as shown in FIG. 2, butwith the operating handle moving in a clockwise direction,

FIG. 4 is an elevation view as in FIG. 3, but with the control leverdisengaged and the operating handle moving in a clockwise direction,

FIG. 5 is an elevation view as in FIG. 4, but with the operating handlemoving in a clockwise direction,

FIG. 6-is an elevationview of the apparatus shown in FIG. 5, with thedual pawl-actuating means out of engagement with the ratchet wheel,

FIG. 7 is an elevation view, in section, of the disc brake of thepresent invention, which view is taken along Section Lines 7-7 of FIG.1,

FIG. 8 is a section-view of the control apparatus taken along SectionLines 8-8 of FIG. 3, but with the control shaft in section,

FIG. 9 is an elevation view, partially in section, showing the actuatingpawl mechanism in one of its counterbalanced positions,

FIG. 10 is an elevation view, partially in section, of a secondembodiment of the actuating means which utilizes two cams,

FIG. 11 is an elevation view, partially in section, of one embodimentfor the double cam arrangement,

FIG. 12 is an elevation view, partially in section, ofa secondembodiment for the double cam arrangement,

FIG. 13 is an elevation view, partially in section, of yet anotherembodiment of the double cam arrangement,

FIG. 14 is a partial elevation view of another embodiment for the doublecam arrangement,

FIG. 15 is a partial elevation view of still another embodiment for thedouble cam arrangement,

FIG. 16 is a perspective view of a lever-actuated chain hoist utilizingthe present invention,

FIG. 17 is a partial side view, in section, showing the actuatingmechanism for the hoist of FIG. 16,

FIG. 18 is a partial end view of the apparatus of FIG. 17 taken alongSection Lines 18-18 of FIG. 17,

FIG. 19 is a partial side view, in section, showing a second embodimentof a chain hoist utilizing the present invention, and

FIG. 20 is a partial end view of the apparatus shown in FIG. 19 andtaken along Section Lines 20-20 of FIG. 19.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS Turning now to FIG. 1,the present invention will be described as it may be applied to aratchet winch. This winch is comprised ofa base plate 10 upstanding fromwhich are two side supports 12, only one of which is shown in FIG. I. Apad eye 14 is attached to the baseplate. This pad cye may be welded orbolted to the deck of a barge, and thereby prevent theft of the winchwhile allowing maneuverability about the U- shaped eye member.

A shaft 16 is rotatably supported between the supports 12. Fixedlyattached to the shaft 16 for rotation therewith is a ratchet wheel 18having teeth 20 on its periphery. A safety guard 19 is positioned overthe ratchet wheel 18, the safety guard being only partially shown inFIG. 1 for purposes of disclosure. Also fixedly attached to the shaft 16but laterally spaced from the ratchet wheel is a handwheel 22. A drum(not shown) is mounted on the shaft 16 between the handwheel 22 and theratchet wheel 18 for receiving the cable 24.

Also located on the support.l2 is a control lever 70 for the disc brakegenerally indicated by the numeral 26, a control lever 28 for theactuating means, and the operating handle 30. The control lever 28 hastwo positions, an engaged position in which it is shown in FIG. 1, and adisengaged position which is shown in dotted lines in FIG. 1, Furtherdetails concerning the operation of the winch disclosed herein may befound in my US. Pat. No. 3,302,93l previously referred to.

Turning now to FIG. 2, the actuating means for the ratchet winch isdisclosed in further detail. A third support member 32 is mounted on thebaseplate l0 and between the upright supports 12 and is used, along withone of the supports 12, to support the actuating means. The operatinghandle 30 and control lever 28 would normally not be shown in this viewdue to the place at which the section view was taken. They have,however, been superimposed in dotted lines to aid in the description ofthe invention.

The operating handle 30 is secured to a rocker shaft 34 which extendsbetween the supports 12 and 32. Two additional shafts 36 and 38 extendthrough the shaft 34 for rotation with the shaft 34. Rotatably mountedon the shaft 36 is a pawl 40; and on the shaft 38, a pawl 42. As will bereadily understood by one skilled in this art, as the operating handle30 is moved in a counterclockwise direction, due to the eccentricpositioning of the shafts 36 and 38 relative to the center of shaft 34,the pawl 40 will move to the left, as viewed in FIG. 2, away from theratchet wheel. During the same motion of the handle, the pawl 42 willmove to the right, thereby engaging a tooth 20c and turning the ratchetwheel in a counterclockwise direction. Movement of the ratchet wheel inthis counterclockwise direction winds the cable onto the winch. Duringthis counterclockwise motion of the operating handle, the

pawl 40 will be moved in the direction of the arrow shown on the pawl 40to engage a following tooth 20a.

Turning now to FIGS. 2-6 and 8, the means for controlling the engagementand disengagement of the pawl 40 and 42 will be described. A controllever 28 is mounted on a shaft 44 which extends through the support 12and has a control cylinder or cam 46 fixedly attached thereto. A secondshaft 48 is attached to the cylinder 46 and provides means for rotatablysupporting a first link 50. It will be noted that both the shaft 44 andthe shaft 48 are eccentrically mounted on the cam 46.

A second link 52 is rotatably connected to the outermost or free end ofthe first link 50. Also connected to this end of the first link is aleaf spring 54. A second leaf spring 56 is connected to the free end ofthe second lever 52. Both of the leaf spring are connected to theirrespective levers in a rotatable manner and are connected to theirrespective pawls by any conventional means such as by screws 58.

A cam surface 60 is mounted on the member 62 which is, in turn,connected to the baseplate 10. The cam surface is positioned adjacentthe lowermost pawl 42, and is comprised of a first portion 64 which isgenerally horizontal, and is somewhat removed from the ratchet wheel.The cam surface is further comprised of an upwardly inclined portion 66which is directed toward the ratchet wheel.

Turning now to FIG. 7, there is shown a section view of the disc brakeutilized with the disclosed winch. This brake is comprised of a controlhandle or knob 70 which is mounted on a shaft 72. The shaft 72 is inthreaded engagement with the upstanding support 12. The innermost end ofthe shaft contains a cylindrical recess 74. A spring 76 is containedwithin this recess, as in a piston 78 which acts as the braking portionagainst the ratchet wheel 18.

Turning now to the operation of the disclosed invention and referringprimarily to FIGS. 26, we will assume that the operator of the winchdesires to take in cable, and thus tighten up the connection between,for example, barges. In the description of the operation, the directionsof movement for the various parts will be the directions as viewed inFIGS. 1- 6. To aid in describing the operation and in claiming theinvention, the word engage and variations thereof will be used todescribe the operative contact between the pawl and tooth, such as theposition of the pawl 42 and tooth 200 shown in FIG. 2. Other contact,such as pawl 40 and tooth 20a in FIG. 2, will be described by use ofcontact." Thus, a pawl is engaged when driving or when braking theratchet wheel.

To take in cable, the operator will turn the control lever 28 to itsengaged position, which is the position shown in FIGS. 1- -3. Byrotating the handwheel 22, he will then take up the slack in the cable24 as far as is possible. When the control lever 28 is in its engagedposition, the spring members 54 and 56 urge the pawls 40 and 42upwardly, and thus bring them into contact with the ratchet wheel 20. Inthis manner, one pawl will always be in an engaging position to act as abrake, thus preventing the cable from unwinding. We will further assumethat the operating handle 30 is in the position shown in dotted lines onFIG. 1. To operate the winching mechanism, the handle will be moved fromthis position in a counterclockwise direction. The movement of therespective portions of the linkage mechanism resulting from thismovement of the handle 30 is shown by the arrows in FIG. 2. Thelowermost pawl 42 will engage and push against the tooth 20c and movethe ratchet wheel 18 in its counterclockwise direction, thus winding thecable in. Simultaneously, the pawl 40 will be move rearwardly, or in thedirection of the arrow shown on it. This pawl will back up until itengages the following tooth 20a.

When the handle 30 has been moved as far as is possible in acounterclockwise direction, its direction will be reversed. Movement inits clockwise direction will result in the movement of the pawls asshown in FIG. 3. The pawl 40 will now be engaged with the tooth 20a andwill move the ratchet wheel in the desired counterclockwise direction.Tooth 42 is moved back to a point at which it will engage tooth 20b, andaccordingly, the winch will be ready for the previously describedcounterclockwise movement of the handle. As will be readily understood,by moving the handle in a reciprocating manner, the ratchet wheel willbe moved in a counterclockwise direction, thus taking in the cable asdesired. As was pointed out previously when the control lever 28 is inits engaged position, the linkage members 50 and 52 are sopositionedrelative to the shaft 34 that their fixedly attached springs 54 and 56will constantly urge the pawls 40 and 42 upwardly against theratchet-wheel so that a pawl will always be engaged to prevent the winchfrom unwinding.

Assuming now that the operator desired to let off the cable on thewinch, the control lever 28 is moved to its disengaged position which isshown in dotted lines in FIGS. 1 and 4-6. When in this position, theforce of the leaf springs is exerted downwardly to urge the pawls 40 and42 away from the ratchet wheel. Should these pawls become immediatelydisengaged, however, and assuming there is no appropriate braking means,the ratchet wheel 18 and connected drum will begin to revolvequiterapidly due to the tension on the cable which could be in excess of90,000 pounds. This uncontrolled unwinding of the, cable would, ofcourse, be undesirable in most instances.

Returning now to FIGS. 46, due to the force exerted by the cable throughthe ratchet wheel, the wheel will remain engaged with the pawl thathappens to be engaged at the time that the lever 28 is moved to itsdisengaged position. Assuming for purposes of explanation that the pawl40 is so engaged with tooth 20a and that handle 50 is in its right-handposition as shown in FIG. 4, the unwinding operation will be described.

To start the unwinding, the handle is moved once again in acounterclockwise direction. As the pawl 40 moves to the left, it willremain engaged with the wheel due to the force exerted against it by thetension in the cable. As will be noted from an examination of the spring54 as viewed in FIG. 4, it is urging the pawl 40 away from the wheel 18,but it is not strong enough to overcome the force exerted against thepawl by the wheel I8. Since no part of the force is exerted against thepawl 42, it will fall onto the portion 64 of the cam surface 60 due tothe action of its spring 56.

When the operating handle 30 nears the end of its counterclockwisemovement, the pawl 42 is moved to the right, or into engagementposition, and contacts the portion 66 of the cam surface. This portion66 will direct the pawl 42 toward the ratchet wheel until it ultimatelycontacts and engages the tooth 20c. At this point, the operating handle30 has reached the end of its counterclockwise movement. The pawl 42thereupon takes the tension exerted through the ratchet wheel andrelieves the pawl 40 which will drop into the position shown in FIG. 5.

The operator then moves the operating handle 30 in its clockwisedirection, resulting in the movement of the pawls and ratchet wheelshown by their respective arrows in FIG. 5. Due to the tension that isstill being exerted by the cable, the pawl 42 will remain engaged withthe tooth 20c. As the handle 30 continues in its clockwise movement, thepawl 42 will move to the left and the pawl 40 to the right, relative toeach other. As will be seen by an examination of FIG. 5, the uppersurface of the pawl 42 acts as a cam to direct the pawl 40 into contactand engagement with the tooth 20b. When the lever 30 reaches the end ofits clockwise travel, the pawl 40 will be engaged with the tooth 20b,and the pawl 42 will retract from the wheel and drop, once again, ontothe portion 64 of the cam surface 60.

The above-described action will continue as the handle 30 isreciprocated until the tension in the cable is reduced to a point thatthe force exerted through the ratchet wheel can no longer overcome theforce exerted on the pawls by the springs 54 and 56. At this point, bothof the pawls 40 and 42 will drop into the position shown in FIG. 6. Thecable is at this point, however, unwound to a relatively slack position,and there is no danger of any rapid rotation or unwinding from thewinch.

It should be pointed out that positive movement of the lever 30 isrequired to unwind the cable where there is sufficient tension in it tocreate the force necessary to retain the pawls in contact. It is forthis reason that the winch cannot unwind itself whether the controllever 28 is in its engaged or disengaged position.

For example, assume that the cable is wound tight and one releases thehandle 30 in the position of FIG. 2. Due to the taut cable, the ratchetwheel will attempt to unwind, and therefore, will rotate in a clockwisedirection until pawl 40 contacts tooth 20b. At this point, both pawlswill be engaged. The force exerted on pawl 40 will tend to rotate therocket shaft 34 and handle 30 in a counterclockwise direction, but theforce exerted on pawl 42 will have the opposite effect. Thus, the forcestransmitted from the wheel 18 to the pawls 40 and 42 will counterbalancethemselves, thereby effectively locking or braking the winch.

To unwind the winch, it is necessary to move the handle 30 from thison-center position far enough that one of the pawls will disengage andfall free. In this way, the winch is unwound, slowly and in a controlledmanner, by reciprocating the handle. Each reciprocal movement of thehandle must, of course, be forced beyond its on-center orcounterbalanced position for the unwinding to occur. FIG. 9 shows such acounterbalanced position and' the arrows on the pawls show the directionin which the forces from the wheel 18 move. It should be noted that thiscounterbalancing exists through a range of positions and not at just onecentral position.

As to the exact positioning and dimensioning of the parts in the doublepawl-actuating means of the present invention, many variables must beconsidered. Among these are: size of the winch or hoist, load to becarried, distance between cam 46 and rocket shaft 34, distance betweenpawls, size and weight of the pawls, strength of springs 54 and 56,length of levers 50 and 52 and at what magnitude of tension remaining inthe cable are the springs to force the pawls out of engagement with theratchet wheel. Accordingly, the size and positioning of the parts willvary depending on ones objectives and needs in the particular winch orhoist being built.

An alternate manner of accomplishing a slow unwinding is by use of thebrake means shown in FIG. 7. By rotating the operating lever 70, thescrew 72 moves further into the support 12, thus bringing the piston 78into contact with the side of the ratchet wheel. The spring 74 may beused to vary the force exerted by the inserton the ratchet wheel, as canbe the knob 70. If desired, the knob 70 can be screwed in sufficientlyto completely halt rotation of the ratchet wheel. In the same manner, itmay be used to provide a varying degree of retarding force, whereby thecable can be unwound slowly and in a controlled manner without the useof the linkage and pawl arrangements, or the linkage and pawlarrangements may be used in conjunction with the brake. The brake will,of course, remove some of the force exerted through the ratchet wheel onthe pawls. Accordingly, the pawls will drop into the position of FIG. 6sooner, due to the fact that the pawls will remain engaged only as longas there is a sufficient force exerted on'at least one of them toovercome the downwardly directed spring force. Thus the pawl arrangementmaybe used, if desired, at the beginning of the unwinding of the cablewhen the tension is greatest, and toward the end, the operator can useonly the brake.

Turning now to FIG. 10, there is shown an embodiment utilizing two camsurfaces rather than the single cam surface 60 discussed in the lastembodiment. In the embodiment of FIG. 10, the control shaft 47 has across-sectional configuration that differs from that of shaft 46 in thelast-discussed embodiment, but the lever 50 is'still eccentricallymounted relative to the shaft axis of rotation.

Discussing now the cam surfaces, these are shown in FIG. 10 in dottedlines. A first cam surface 80 corresponds with the single cam surface 60of the first embodiment. The second cam surface is indicated by thenumeral 82. The configuration of the cam surfaces 80 and 82 differ fromthe configuration of cam surface 60, and it should perhaps be pointedout here that various configurations can be used for the cam surfacesand achieve the same results. It is only necessary that the rise at theouter ends of the cams be sufficiently high to insure engagement withthe ratchet wheel 18 by the pawl, and that the rearward portion of thecams be sufficiently removed from the ratchet wheel to insure that thepawl will not engage the wheel. In this embodiment, the cam surfaces 80and 82 are positioned beside their respective pawls, and pins 84, actingas cam followers, extend laterally from the pawls to ride on the camsurfaces.

Since the first-discussed embodiment of the invention utilizing only onesurface kept its pawls engaged only so long as tension remained in theratchet wheel, problems are presented should the tension be relivedmomentarily and then reexerted on the winch or hoist. This isparticularly a problem with regard to hoists since the object beinglifted could momentarily strike a ledge, table or the like, thusrelieving the tension for a sufficient length of time for the pawls todrop away from the ratchet wheel. The result will be the freewheelingrelease of the object being hoisted.

This is prevented, however, by the construction of the presentinvention, as is shown in FIG. 10. As can be seen in FIG. 10, the pawl40 is not in contact or engaged with the tooth 20a, and the pawl 42 isremoved from its engaged position. Even though neither pawl contacts theratchet wheel, the cam 82 insures that the pawl 40 is adjacent theratchet wheel, so that should the wheel begin to turn quickly in aclockwise direction, or unwind, pawl 40 will immediately become engagedwith tooth 20a. This will prevent any rapid release or unwinding sincethe pawl 42 would then be moved forward so that it would engage tooth20c. Thus an on-center or counterbalanced position would be assumed,wherein both pawls are engaged and act to counterbalance each other,preventing the unwinding of the ratchet wheel absent positive movementor displacement of the lever 30. Due to the use of the two earns 80 and82 and their configuration, at least one of the pawls will always remainin an engaging position. Thus freewheeling release or unwinding isprevented by the use of these structures shown in this embodiment. Itshould be noted that the position of the pawls shown in FIG. 10, whereinneither pawl is in contact with the ratchet wheel, will be assumed onlywhen no tension is exerted on the ratchet wheel, or when the tension istaken up by some other means, such as the brake 26 (see FIG. 7) or thepawl 154 (see FIG. 19). It is this latter situation that the double camarrangement becomes important to prevent freewheeling should thebrake 26or the pawl 154 be accidentally released.

Various arrangements for the cam surfaces 80 and 82 are shown in FIGS.11-15. For purposes ofillustration and clarity, the pawls and otherapparatus are shown in some of these FIGURES only in broken lines andnot shown at all in others. In FIG. 11, the earns 80 and 82 are part ofa solid block 86 which is slidably mounted on a surface 88. This surfacemay be the baseplate of the winch or any other suitable surface. Aneccentrically mounted cam 90 is positioned adjacent the block 86 formoving it into its engaged position, which is that shown in FIG. 11. Aforward stop 92 is fixedly secured to plate 88, and aligned passagewaysare located in both the stop 92 and the block 86. A guide pin 94 ispositioned in the passageway, as is a spring 96. The cam 90 is actuatedby a lever 100 (see FIG. 16). In operation, it may be desirable toremove the cam surfaces 80 and 82 from their operative position. This isespecially true when a free release is desired or during the winding orhoisting operations, since they are not needed when the control lever 28is in its engaged position. To move the cam surfaces into theiroperative positions, it is merely necessary to rotate the lever 100,moving the cam 90 about its eccentric axis. This will slide the block 86toward the forward stop, the block being guided by the guide pin 94. Theforward stop will properly position the cam surfaces 80 and 82. To movethe cam surfaces out of their operative position, the rotation of thehandle 100 will release the force exerted by the cam 90, and the spring94 will slide the block 86 to the left as viewed in FIG. 11.

The embodiment shown in FIG. 12 is quite similar to that of FIG. 11 withthe exception that spring members are used for the cam surfaces and 82.These spring members are mounted on spring mounts 102, and ride on theblock 98 which has camming surfaces as its upper surface to properlyposition the earns 80 and 82. The operation of this embodiment is thesame as FIG. 11 with the exception that, when the block 98 is moved toits inoperative position, the spring cam members 80 and 82 movedownwardly to their inoperative position.

FIG. 13 shows another embodiment for the cam surfaces utilizing springmembers mounted, once again, on spring mounts 102. These springs areconnected at 104, and the cam acts directly on this spring portion 104to raise or lower the cam surfaces into their operative and inoperativepositions, respectively. FIG. 14 shows an embodiment similar to that ofFIG. 13 but having a linkage arrangement 106 substituted for the cam 90and spring portion 104 of FIG. 13. The linkage arrangement 106 rotatesabout the axes I08 and 110 to raise and lower the earns 80 and 82. Inthe embodiment of FIG. 15, the cam 90 is again used and includes thereona protuberance 112. The spring cams 80 and 82 are once again joined andare fixedly attached to this protuberance 112. As can be seen in FIG.15, this protuberance is eccentric relative to the axis about which thecam 90 rotates, thus providing means to raise and lower the camsurfaces.

Any of the above disclosed embodiments could be used with a variousassortment of configurations for the cam surfaces, and any of the camsurface arrangements may be employed on winches, hoists or the like. Itwill be readily understood, of course, that various other arrangementscould be used for the configuration of the cam surfaces themselves, aswell as for the arrangement of elements necessary to properly positionthe cam surfaces, and if desired, to remove them to an inoperativeposition.

Turning now to FIG. 16, there is illustrated a lever actuated chainhoist generally indicated by the numeral 120. Such devices are generallywell known in the art, and accordingly,

need only a basic description here. Generally, therefore, they arecomprised ofa hook 122 for attaching the hoist to a beam or othersupport. Frame members 124 are connected to the top of two side frameplates 126, only one of which is shown in FIG. 16. Rotatably mounted inthese frame members 126 is a shaft 128 about which is wrapped the chainor cable 130 which is used for the hoisting work. A cover 132 ispositioned on the near end of the hoist as viewed in FIG. 16 and coversthe operating mechanism of the hoist. A lever 134 having a handle 136 ispositioned outside the cover 132, and by rotating this handle, thewinching or hoisting action takes place. The pawl control lever 28 isalso positioned on the outside of this cover, as is the cam surfacecontrol lever 100. Stops 138 are located on the cover to properlyposition the control lever 28.

Discussing now FIGS. 17 and 18, in FIG. 17 the cover 132 and framemember 126 are only partially shown so that we may more clearlyillustrate the operative elements of the hoist. In addition, the handle134 is broken away so that the pawl and cam arrangement may be shown.The particular pawl arrangement is identical to that shown in FIG. 10,and the arrangement for the cam surfaces 80 and 82 are the same as thatshown in FIG. 13. These have simply been incorporated here to provideone arrangement that will produce satisfactory results in such a leveractuated chain hoist. The control lever 28 is in its disengagedposition, as is the lever 100.

To provide proper support for the operative elements of the hoist, abottom plate 88 is attached to the frame member 126 and an upstandingplate 138 extends from the other end of the bottom plate 88. The plates138 and 126 are essentially parallel and provide the two uprightsbetween which the rocker shaft 34 is journaled by any appropriate meanswell known in the prior art.

To operate the chain hoist, the handle 134 is reciprocated as shown bythe arrow positioned at its outermost end. When the lever 28 is in itsengaged position (shown in dotted lines in FIG. 17), pawls 40 and 42will rotate the ratchet gear 18 in a counterclockwise direction, therebywinding the chain in. To lower the object being hoisted, the controllever 28 is moved to its inoperative position (shown in FIG. 17), andthe handle 134 is again reciprocated. As with the previously discussedratchet winch, this will unwind the hoist in a slow and controlledmanner. It should perhaps be pointed out that the down position of lever28 in the embodiments of FIGS. 16- is the disengaged position, whereasit was the engaged position in the earlier discussed winch. This, ofcourse, is merely a matter of choice in arranging the various elementsof the invention.

The object being lifted can be suspended in the air by release of thelever 134, which will allow the ratchet wheel 18 to rotate in aclockwise direction until both pawls 40 and 42 contact the ratchetwheel. The pawls will, thereupon, assume their on-center orcounterbalanced position, each acting against the other to prevent theunwinding of the chain. This was discussed previously with regard to thewinch. As has also been previously pointed out, to unwind the hoist itis necessary to move the operative elements past their counterbalancedposition during each reciprocal movement of the lever 134. Thus,positive handle action is required for unwinding purposes, therebypreventing free or unexpected release of the chain.

Turning now to FIGS. 19 and 20, a third embodiment of the presentinvention will be discussed, which embodiment is generally indicated bythe numeral 140 and. is characterized as being a handwheel-actuatedhoistv As with FIG. 17, the frame and cover portions of FIG. 19 havebeen broken away for purposes of illustration. In a similar manner, thehandwheel is also only partially shown. The general configuration ofthis hoist 140 is essentially the same as shown in FIG. 16 with theexception that a handwheel 142 extends through the cover 132. The pawlarrangement as to the rocket shaft and the cam surfaces 80 and 82 arethe same as those in FIG. 17. Additional apparatus is required for thisembodiment and to support this,

the bottom frame member 88 is extended beyond the frame member 126 asbest shown in FIG. 20. Upstanding from the side of plate 88 oppositeplate 138 is yet another upstanding member 144. As shown in broken linesin FIG. 19, this plate 144 need only be a small plate, thus decreasingthe material cost and the weight of the hoist. .lournaled in the plate144 is a shaft 148 which is the axis of rotation for the handwheel 142.A ratchet drive gear 146 is mounted about shaft 148 between plates 144and 126. A connecting arm 150 is rotatably secured by one of its ends149 to the ratchet gear 146. Rotatably connected at the opposite end ofthe arm 150 is a drive arm or lever 152, the opposite end of which isconcentrically mounted on the rocker shaft 34.

One additional feature of the apparatus shown in FIGS. 19 and 20 is theaddition of the ratchet brake pawl 154. A spring 155 urges the pawltoward the hear 146. This pawl is rotatably mounted on the plate 144 andis controlled by the lever 156 to which it is attached by means ofspring 158. A stop 159 is located on the outside of the cover againstwhich the lever 156 acts when moving the ratchet pawl 154 to itsinoperative position. It is shown in FIG. 19 in its operative or lockingposition. The spring 158 is attached eccentrically to the axis ofrotation for the lever 156. This is accomplished by either attaching thespring at a point spaced from the axis of rotation for lever 156 or elseby use ofa cam such as 160.

Turning now to the operation of the embodiment shown in FIGS. 19 and 20,and assuming that the control lever 28 is in its engaged position (shownin broken lines in FIG. 19), rotation of the handwheel in a clockwisedirection (when viewed as in FIG. 19) will rotate the ratchet drive gear146 also in a clockwise direction. This will cause the end 149 to movein a circle having itscenter concentric with shaft 148. This motion willbe transmitted to the lever arm 152, causing it to reciprocate as didthe lever 134 of the embodiment of FIGS. l6-18. This reciprocal actionof lever arm 152 results in the reciprocal back and forth movement ofthe pawls 40 and 42. The result is, of course, the movement of theratchet wheel 18 in a counterclockwise direction, thereby winding up thechain. To unwind the chain, the control lever 28 is moved to isdisengaged position (that shown in FIG. 19) and the handwheel 142 isagain rotated in its clockwise direction. Once again, positive action bythe handwheel is required to cause an unwinding or clockwise rotation ofthe ratchet wheel 18. Otherwise the counterbalancing effect of the pawls40 and 42 will take place to hold the ratchet wheel 18 stationary.

It may be desired in hoisting an object to adjust the height to which itis lifted by only a slight amount. Using only the actuating pawlarrangement as a braking means would give only rough adjustment of thisheight. In other words, a full reciprocal movement of the lever 152 musttake place to vary the height and still utilize the counterbalancingbraking function of the drive pawls 40 and 42. With the use of the pawl154 cooperating with the ratchet gear 146, however, fine adjustments inthe height can be made.

Assume, for example, that an object is being lifted and the operatingapparatus of the hoist is in the position shown in FIG. 19 at thedesired height. The pawl .154 acting against the teeth of the ratchetgear 146 will prevent any further rotation or unwinding of the hoist. Itis obvious from an examination of the pawls 40 and 42 in FIG. 19 (ascompared to that in FIG. 9) that they are not in their counterbalancingposition. Accordingly, should they be relied on for the braking of thehoist, a certain amount of rotation of the ratchet wheel 18 will have tooccur for the pawls 40 and 42 to achieve their on-center position. Pawl154 will, however, hold in its present position.

Assuming one desires to make a slight adjustment upwardly, one needmerely move the control lever 28 to its engaged position and rotate thehandwheel 42 until the pawl 154 engages the next subsequent tooth on theratchet gear 146. The spring 155 will yield to allow the pawl 154 toride over the teeth. To lower by a limited amount the object beinglifted, one merely places the control lever 28 in its disengagedposition and then turn the handwheel 142 clockwise. Thus, the object maybe either raised or lowered an amount depending upon the distance apartthat the teeth are located on the ratchet gear 146. The distance of theteeth may, of course, be changed as desired, thereby giving the hoistfiner or rougher adjustment capacity as desired.

It should be pointed out that sudden jerks or pulls may be exerted onthe winch by the barge train or tug boats which will create tremendousforces on the pawls. Accordingly, it is desirable to use thecounterbalancing method of braking the winch and holding it stationary,since the force to be overcome will be divided between the two pawls 40and 42. Thus, it is better capable of taking such extreme shock forces.With the hoist, the force will be steady, the only force being exertedbeing the weight of the object that is being lifted. Since this weightis lifted alternately by only one of the pawls40 or 42, one pawl will besufficient to hold or brake this load. Ac.- cordingly, the single pawl154 is sufficient. It is to be understood, however, that the arrangementhaving the braking pawl 154 and the ratchet gear 146 can be used on awinch if desired, especially when the unexpected large shock loads willnot be experienced.

To release the pawl 154, one need merely rotate the control lever 156until it contacts stop 159. The spring 158 linking .the pawl 154 withthe cam 160 will'rotate the pawl out of contact with the ratchet gear146. With the pawl 154 out of engagement with the ratchet gear 146, thehandwheel 142 can be rotated either clockwise or counterclockwise. Thehoist (and winch if such a wheel be used on a winch) will take or letout depending on the position of lever 28, rather than the direction ofrotation of the wheel 142.

It is, of course, to be understood that in lieu of the: handwheel 142, aconventional chain-driven wheel may be substituted. Such chainwheels aregenerally utilized where the hoist is at such a height that it cannot bereached by the operator. When the hoist is being used at such a height,suitable extensions, rods or other means must be utilized to manipulatethe levers 28,100 or 156.

The various embodiments of the actuating pawl arrangement and camsurfaces disclosed herein may also be used with a mechanized winch orhoist. One skilled in this art can readily conceive of the applicationof a powered unit utilizing the various arrangements disclosed herein.One such piece of equipment to actuate the winch or hoist would be ahydraulic rotary actuator, such as those produced by HoudailleHydraulics of Buffalo, New York and disclosed in their catalogue HYD-4.Such apparatus produces a reciprocal rotary motion through an arc ofsufficient length to bring about the necessary reciprocal action neededfor the shaft 34 and the pawls 40 and 42. The rotary actuator could alsohe used either directly with the rocker shaft 34 or with appropriatelinkage means to transmit this reciprocal rotary motion to the rockershaft. Reciprocal action could also be produced by the use of ahydraulic cylinder cooperating with a lever arm attached to the rockershaft 34.

As can be seen, therefore, the present invention achieves the objectivesset forth at the outset. Apparatus has been devised which is easy tooperate and manufacture and which reliably actuates ratchet winches orhoists, both in the taking up and letting out of the cable or chain.Accurate control can be exercised over both the taking up and lettingout. Linkage means are utilized with which the operator can selectivelyengage or disengage the pawls from the ratchet wheel, thereby switchingfrom a taking in operation to one letting out the cable or chain. Camsurfaces have been incorporated to insure against a run away orfreewheeling release of the taut cable or chain. Means have also beendisclosed showing a variety of arrangements for the various parts ofthis apparatus. Apparatus has also been described which will providefine adjustment in the lifting or lowering, or the taking in or lettingout of the cable. The apparatus of the present invention and varioussubcombinations of the disclosed apparatus may be used on a variety ofhoists, winches and the like which utilize a ratchet wheel, regardlessof the type of equipment it is. In the appended claims, therefore, thewords winch or hoist are intended to be interchangeable, and thusinclude each other, and other similar types of equipment using a ratchetwheel as its driving means.

The present invention, therefore, is well adapted to carry out theobjects and obtain the ends and advantages mentioned as well as othersinherent therein. While a presently preferred embodiment of theinvention has been given for the purpose of disclosure, numerous changesin the details of construction, the combination, shape, size andarrangement of parts may be resorted to without departing from thespirit and scope of the invention as hereinafter claimed.

lclaim:

l. A ratchet winch including two substantially parallel supports,

a shaft extending between said supports,

a drum,

a ratchet wheel, both the wheel and the drum being fixed to said shaft,

a rocker shaft rotatably mounted on the winch,

means for rocking said shaft,

dual pawls eccentrically and pivotally mounted on said rocker shaft forengagement with the ratchet wheel,

a control shaft mounted on the ratchet winch for rotation about a firsteccentric axis,

means for rotating the control shaft about said axis into first andsecond positions,

linkage means including spring members and a plurality of articulatedlink members connected end to end and connecting the spring members tothe control shaft, said linage means being eccentrically mounted on thecontrol shaft for engaging the pawls with the ratchet wheel when thecontrol shaft is in its first position, and

cam surface means mounted on the ratchet winch adjacent one of saidpawls for directing said one pawl to the ratchet wheel when the controlshaft is rotated into its second position.

2. The invention of claim 1 wherein the cam surface means is defined asincluding,

a first portion removed from the ratchet wheel, and

a second portion directed toward the ratchet wheel, said one pawl beingsupported by a portion of the cam surface means when the control shaftis rotated into its second position, except when said one pawl isengaged with the ratchet wheel.

3. The invention of claim 2 wherein the means for rocking the rockershaft includes,

a ratchet gear rotatably mounted on said winch,

means for rotating the ratchet gear,

second linkage means connecting the rocker shaft to said ratchet gearfor rocking the rocker shaft as the gear rotates, and

braking pawl means movable into engagement with the teeth of saidratchet gear for locking the gear, and in turn, the second linkage meansand rocker shaft.

4. The invention of claim 3 wherein said braking pawl means is yieldablybiased against said ratchet gear teeth to allow rotation of the gear inone direction but to prevent rotation in the direction opposite said onedirection.

5. A ratchet winch including,

two substantially parallel supports,

a shaft extending between said supports,

a drum,

a ratchet wheel, both the wheel and the drum being fixed to said shaft,

a rocker shaft rotatably mounted on the winch,

means for rocking said shaft,

dual pawls eccentrically and pivotally mounted on said rocker shaft forengagement with the ratchet wheel,

a control shaft mounted on the ratchet winch for rotation about a firsteccentric axis,

means for rotating the control shaft about said axis into first andsecond positions,

linkage means eccentrically mounted on the control shaft including aspring connected to each of the pawls for engaging the pawls in theratchet wheel when the control shaft is in its first position,

cam surface means mounted on the ratchet winch adjacent one of saidpawls for directing said one pawl to the ratchet wheel when the controlshaft is rotated into its second position, said linkage means including,

a first link rotatably attached by one of its ends to the control shaftabout a second axis eccentric to the control shaft,

a second link rotatably attached by one of its ends to the other end ofthe first link, I

one of said springs being attached to the other end of the first linkand the other of said pawls,

the second of said springs being attached to the other end of the secondlink and connected to said one pawl, said springs urging the pawlsagainst the ratchet wheel when the control shaft is in its firstposition and away from the wheel when the control shaft is in its secondposition.

6. The invention of claim 5 and further including,

brake means for retarding rotation of the ratchet wheel comprised of,

a control rod extending through and threadedly engaging one of saidsupports,

a free end on said rod for contact with the ratchet wheel, wherebypressure by the brake means against the wheel may be varied by rotationof the control rod through said one support.

7. The invention of claim 6 and further including,

a recess in said free end,

a spring in said recess, and

a piston in said recess contacting said spring and extending beyond saidfree end for contact with the side of the ratchet wheel.

8. The invention of claim 1 wherein said cam surface means is defined asbeing comprised of,

a first cam adjacent said one pawl and further including,

a second cam adjacent the other of said pawls for directing said otherpawl to the ratchet wheel when the control shaft is rotated into itssecond position.

9, The invention of claim 8 wherein said first and second cams aredefined as each having,

a first portion removed from the ratchet wheel, and

a second portion directed toward the ratchet wheel, said pawls beingsupported by one of said portions of their respective cams when thecontrol shaft is rotated into its second position, except when engagedwith the ratchet wheel.

10. The-invention of claim 9 wherein the linkage means is furtherdefined as including,

a first link rotatably attached by one of its ends to the control shaftabout a second axis eccentric to the control shaft,

a second link rotatably attached by one of its ends to the other end ofthe first link,

one of said leaf springs being attached to the other end of the firstlink and the other of said pawls,

the second of said leaf springs being attached to the other end of thesecond link and connected to said one pawl, said leaf spring urging thepawls against the ratchet wheel when the control shaft is in its firstposition and away from the wheel when the control shaft is in its secondposition.

11. In a ratchet winch including,

essentially parallel side members,

a drum, and

a ratchet wheel secured to a shaft rotatably mounted between said sidemembers,

dual pawls,

reciprocating means for driving the ratchet wheel by alternateengagement and disengagement of the dual pawls with the ratchet wheel,

control means including,

a control lever rotatable to first and second positions, and

having a control shaft for rotation therewith,

linkage means including spring members and a plurality of articulatedlink members connected end to end and connecting the spring members tothe control shaft, said linkage means being operatively connected to thecontrol lever for maintaining contact between at least one or the otherof the dual pawls and the ratchet wheel when the control lever is in itsfirst position, and

cam means positioned on said winch adjacent one of said pawls fordirecting said one pawl into contact with the ratchet wheel when thecontrol lever is in its second position and the reciprocating meansmoves said one pawl into engagement position.

12. The invention of claim 11 wherein the cam means is defined asincluding,

a first portion removed from the ratchet wheel, and

a second portion directed toward the ratchet wheel, said one pawl beingsupported by a portion of the cam means when the control lever is in itssecond position except when said one, pawl is engaged with the ratchetwheel.

113. In a ratchet winch including,

essentially parallel side members,

a drum and,

a ratchet wheel secured to a shaft rotatably mounted between said sidemembers,

dual pawls,

reciprocating means for driving the ratchet wheel by alternateengagement and disengagement of the dual pawls with the ratchet wheel,

control meansincluding,

a control lever rotatable'to first and second positions,

linkage means operatively connected to the control lever for maintainingcontact between at least one or the other of the dual pawls and theratchet wheel when the control lever is in its first position,

cam means positioned on said winch adjacent one of said pawls fordirecting said one pawl into contact with the ratchet wheel when thecontrol lever is in its second position and the reciprocating meansmoves said one pawl into engagement position,

Said linkage means further including,

a leaf spring connected to each of the pawls,

a control shaft attached to the ratchet winch and operatively connectedto the control lever for movement by the lever about a first eccentricaxis,

a first link rotatably connected by one ofits ends to the control shaftabout a second axis eccentric to the control shaft,

a second link rotatably connected by one of its ends to the other end ofthe first link,

one of said leaf springs being connected to the other end of the secondlink and said one pawl,

the other of said leaf springs being connected to said other end of thefirst link and the other of said pawls.

14. The invention of claim 12 wherein the reciprocating means includes,

a rocker shaft,

a ratchet gear rotatably mounted on said winch,

means for rotating the ratchet gear,

second linkage means connecting the rocker shaft to said ratchet gearfor rocking the rocker shaft as the gear rotates, and

braking pawl means moveable into engagement with the teeth of saidratchet gear for locking the gear, and in turn, the second linkage meansand rocker shaft.

15. The invention of claim 14 wherein said braking pawl means isyieldably biased against said ratchet gear teeth to allow rotation ofthe gear in one direction but to prevent rotation in the directionopposite said one direction.

16. The invention of claim 11 wherein the cam means is further definedas directing both pawls and including,

a first cam surface adjacent said one pawl,

a second cam surface adjacent the other of said pawls, both cam surfacesbeing sufficiently close to the ratchet wheel to insure engagement withthe ratchet wheel by the pawl that is positioned for engagement by thereciprocating means.

17. The invention of claim 16 wherein the linkage means is defined asincluding,

a leaf spring connected to each of the pawls,

a control shaft attached to the ratchet winch and operatively connectedto the control lever for movement by the lever about a first eccentricaxis,

a first link rotatably connected by one of its ends to the control shaftabout a second axis eccentric to the control shaft,

a second link rotatably connected by one of its ends to the other end ofthe first link,

one of said leaf springs being connected to the other end of the secondlink and said one pawl,

the other of said leaf springs being connected to said other end of thefirst link and the other of said pawls.

18. A control linkage device for expeditiously positioning crankassembly dual pawls for engagement as well as-disengagement with theratchet wheel of a ratchet winch, including,

a shaft mounted to the ratchet winch for rotation about a firsteccentric axis,

means for rotating the shaft about the eccentric axis-to first andsecond positions for engaging and disengaging the pawls, respectively,

a first link rotatably connected at one of its ends tothe shaft about asecond axis eccentric to said shaft,

a second link pivotably attached by one of its ends to the other end ofthe first link, each of said links having attached to their other ends,

spring means each being connected to one of said pawls for urging thepawls against the ratchet wheel when the shaft is in its first positionand away from the ratchet wheel when the shaft is in its secondposition,

19. The invention of claim 18 and including,

cam surface means positioned adjacent one of said pawls for guiding saidone pawl toward the wheel when the shaft is in its second position.

20. The invention of claim 18 and including,

cam means provided adjacent each of said pawls for constantlymaintaining at least one of the dual pawls in position for engagementwith the ratchet wheel when the shaft is in its second position.

21. The invention of claim 20 wherein the cam means is defined asincluding,

a first cam positioned adjacent one of said pawls,

a second cam positioned adjacent the other of said pawls, a portion ofeach of the cams being spaced sufficiently close to the ratchet wheel toengage its respective pawl with the wheel when the pawl contacts saidportion of its respective cam.

22. The invention of claim 18 wherein the spring means is furtherdefined as,

a first spring connected to the other end of said first link and to oneof said pawls, and

a second spring connected to the other end of said second link and tothe other of said pawls.

23. A control linkage device for expeditiously positioning crankassembly dual pawls for engagement as well as disengagement with theratchet wheel ofa ratchet winch, including,

a shaft mounted to the ratchet winch for rotation about a first axis,

means for rotating the shaft about the first axis to first and secondpositions for engaging and disengaging the pawls, respectively,

a first link rotatably connected at one of its ends to the shaft about asecond axis which is eccentric to said shaft,

a second link pivotably attached by one of its ends to the other end ofthe first link, each of said links having attached to their other ends,

spring means each being connected to one of said pawls for urging thepawls against the ratchet wheel when the shaft is in its first positionand away from the ratchet wheel when the shaft is in its secondposition.

24. The invention of claim 23 and including,

cam surface means positioned adjacent one of said pawls for guiding saidone pawl toward the wheel when the shaft is in its second position.

25. The invention of claim 23 wherein the spring means is furtherdefined as,

a first spring connected to the other end of said first link and to oneof said pawls, and

a second spring connected to the other end of said second link and tothe other of said pawls.

1. A ratchet winch including two substantially parallel supports, ashaft extending between said supports, a drum, a ratchet wheel, both thewheel and the drum being fixed to said shaft, a rocker shaft rotatablymounted on the winch, means for rocking said shaft, dual pawlseccentrically and pivotally mounted on said rocker shaft for engagementwith the ratchet wheel, a control shaft mounted on the ratchet winch forrotation about a first eccentric axis, means for rotating the controlshaft about said axis into first and second positions, linkage meansincluding spring members and a plurality of articulated link membersconnected end to end and connecting the spring members to the controlshaft, said linage means being eccentrically mounted on the controlshaft for engaging the pawls with the ratchet wheel when the controlshaft is in its first position, and cam surface means mounted on theratchet winch adjacent one of said pawls for directing said one pawl tothe ratchet wheel when the control shaft is rotated into its secondposition.
 2. The invention of claim 1 wherein the cam surface means isdefined as including, a first portion removed from the ratchet wheel,and a second portion directed toward the ratchet wheel, said one pawlbeing supported by a portion of the cam surface means when the controlshaft is rotated into its secoNd position, except when said one pawl isengaged with the ratchet wheel.
 3. The invention of claim 2 wherein themeans for rocking the rocker shaft includes, a ratchet gear rotatablymounted on said winch, means for rotating the ratchet gear, secondlinkage means connecting the rocker shaft to said ratchet gear forrocking the rocker shaft as the gear rotates, and braking pawl meansmovable into engagement with the teeth of said ratchet gear for lockingthe gear, and in turn, the second linkage means and rocker shaft.
 4. Theinvention of claim 3 wherein said braking pawl means is yieldably biasedagainst said ratchet gear teeth to allow rotation of the gear in onedirection but to prevent rotation in the direction opposite said onedirection.
 5. A ratchet winch including, two substantially parallelsupports, a shaft extending between said supports, a drum, a ratchetwheel, both the wheel and the drum being fixed to said shaft, a rockershaft rotatably mounted on the winch, means for rocking said shaft, dualpawls eccentrically and pivotally mounted on said rocker shaft forengagement with the ratchet wheel, a control shaft mounted on theratchet winch for rotation about a first eccentric axis, means forrotating the control shaft about said axis into first and secondpositions, linkage means eccentrically mounted on the control shaftincluding a spring connected to each of the pawls for engaging the pawlsin the ratchet wheel when the control shaft is in its first position,cam surface means mounted on the ratchet winch adjacent one of saidpawls for directing said one pawl to the ratchet wheel when the controlshaft is rotated into its second position, said linkage means including,a first link rotatably attached by one of its ends to the control shaftabout a second axis eccentric to the control shaft, a second linkrotatably attached by one of its ends to the other end of the firstlink, one of said springs being attached to the other end of the firstlink and the other of said pawls, the second of said springs beingattached to the other end of the second link and connected to said onepawl, said springs urging the pawls against the ratchet wheel when thecontrol shaft is in its first position and away from the wheel when thecontrol shaft is in its second position.
 6. The invention of claim 5 andfurther including, brake means for retarding rotation of the ratchetwheel comprised of, a control rod extending through and threadedlyengaging one of said supports, a free end on said rod for contact withthe ratchet wheel, whereby pressure by the brake means against the wheelmay be varied by rotation of the control rod through said one support.7. The invention of claim 6 and further including, a recess in said freeend, a spring in said recess, and a piston in said recess contactingsaid spring and extending beyond said free end for contact with the sideof the ratchet wheel.
 8. The invention of claim 1 wherein said camsurface means is defined as being comprised of, a first cam adjacentsaid one pawl and further including, a second cam adjacent the other ofsaid pawls for directing said other pawl to the ratchet wheel when thecontrol shaft is rotated into its second position.
 9. The invention ofclaim 8 wherein said first and second cams are defined as each having, afirst portion removed from the ratchet wheel, and a second portiondirected toward the ratchet wheel, said pawls being supported by one ofsaid portions of their respective cams when the control shaft is rotatedinto its second position, except when engaged with the ratchet wheel.10. The invention of claim 9 wherein the linkage means is furtherdefined as including, a first link rotatably attached by one of its endsto the control shaft about a second axis eccentric to the control shaft,a second link rotatably attached by oNe of its ends to the other end ofthe first link, one of said leaf springs being attached to the other endof the first link and the other of said pawls, the second of said leafsprings being attached to the other end of the second link and connectedto said one pawl, said leaf spring urging the pawls against the ratchetwheel when the control shaft is in its first position and away from thewheel when the control shaft is in its second position.
 11. In a ratchetwinch including, essentially parallel side members, a drum, and aratchet wheel secured to a shaft rotatably mounted between said sidemembers, dual pawls, reciprocating means for driving the ratchet wheelby alternate engagement and disengagement of the dual pawls with theratchet wheel, control means including, a control lever rotatable tofirst and second positions, and having a control shaft for rotationtherewith, linkage means including spring members and a plurality ofarticulated link members connected end to end and connecting the springmembers to the control shaft, said linkage means being operativelyconnected to the control lever for maintaining contact between at leastone or the other of the dual pawls and the ratchet wheel when thecontrol lever is in its first position, and cam means positioned on saidwinch adjacent one of said pawls for directing said one pawl intocontact with the ratchet wheel when the control lever is in its secondposition and the reciprocating means moves said one pawl into engagementposition.
 12. The invention of claim 11 wherein the cam means is definedas including, a first portion removed from the ratchet wheel, and asecond portion directed toward the ratchet wheel, said one pawl beingsupported by a portion of the cam means when the control lever is in itssecond position except when said one pawl is engaged with the ratchetwheel.
 13. In a ratchet winch including, essentially parallel sidemembers, a drum and, a ratchet wheel secured to a shaft rotatablymounted between said side members, dual pawls, reciprocating means fordriving the ratchet wheel by alternate engagement and disengagement ofthe dual pawls with the ratchet wheel, control means including, acontrol lever rotatable to first and second positions, linkage meansoperatively connected to the control lever for maintaining contactbetween at least one or the other of the dual pawls and the ratchetwheel when the control lever is in its first position, cam meanspositioned on said winch adjacent one of said pawls for directing saidone pawl into contact with the ratchet wheel when the control lever isin its second position and the reciprocating means moves said one pawlinto engagement position, Said linkage means further including, a leafspring connected to each of the pawls, a control shaft attached to theratchet winch and operatively connected to the control lever formovement by the lever about a first eccentric axis, a first linkrotatably connected by one of its ends to the control shaft about asecond axis eccentric to the control shaft, a second link rotatablyconnected by one of its ends to the other end of the first link, one ofsaid leaf springs being connected to the other end of the second linkand said one pawl, the other of said leaf springs being connected tosaid other end of the first link and the other of said pawls.
 14. Theinvention of claim 12 wherein the reciprocating means includes, a rockershaft, a ratchet gear rotatably mounted on said winch, means forrotating the ratchet gear, second linkage means connecting the rockershaft to said ratchet gear for rocking the rocker shaft as the gearrotates, and braking pawl means moveable into engagement with the teethof said ratchet gear for locking the gear, and in turn, the secondlinkage means and rocker shaft.
 15. The Invention of claim 14 whereinsaid braking pawl means is yieldably biased against said ratchet gearteeth to allow rotation of the gear in one direction but to preventrotation in the direction opposite said one direction.
 16. The inventionof claim 11 wherein the cam means is further defined as directing bothpawls and including, a first cam surface adjacent said one pawl, asecond cam surface adjacent the other of said pawls, both cam surfacesbeing sufficiently close to the ratchet wheel to insure engagement withthe ratchet wheel by the pawl that is positioned for engagement by thereciprocating means.
 17. The invention of claim 16 wherein the linkagemeans is defined as including, a leaf spring connected to each of thepawls, a control shaft attached to the ratchet winch and operativelyconnected to the control lever for movement by the lever about a firsteccentric axis, a first link rotatably connected by one of its ends tothe control shaft about a second axis eccentric to the control shaft, asecond link rotatably connected by one of its ends to the other end ofthe first link, one of said leaf springs being connected to the otherend of the second link and said one pawl, the other of said leaf springsbeing connected to said other end of the first link and the other ofsaid pawls.
 18. A control linkage device for expeditiously positioningcrank assembly dual pawls for engagement as well as disengagement withthe ratchet wheel of a ratchet winch, including, a shaft mounted to theratchet winch for rotation about a first eccentric axis, means forrotating the shaft about the eccentric axis to first and secondpositions for engaging and disengaging the pawls, respectively, a firstlink rotatably connected at one of its ends to the shaft about a secondaxis eccentric to said shaft, a second link pivotably attached by one ofits ends to the other end of the first link, each of said links havingattached to their other ends, spring means each being connected to oneof said pawls for urging the pawls against the ratchet wheel when theshaft is in its first position and away from the ratchet wheel when theshaft is in its second position,
 19. The invention of claim 18 andincluding, cam surface means positioned adjacent one of said pawls forguiding said one pawl toward the wheel when the shaft is in its secondposition.
 20. The invention of claim 18 and including, cam meansprovided adjacent each of said pawls for constantly maintaining at leastone of the dual pawls in position for engagement with the ratchet wheelwhen the shaft is in its second position.
 21. The invention of claim 20wherein the cam means is defined as including, a first cam positionedadjacent one of said pawls, a second cam positioned adjacent the otherof said pawls, a portion of each of the cams being spaced sufficientlyclose to the ratchet wheel to engage its respective pawl with the wheelwhen the pawl contacts said portion of its respective cam.
 22. Theinvention of claim 18 wherein the spring means is further defined as, afirst spring connected to the other end of said first link and to one ofsaid pawls, and a second spring connected to the other end of saidsecond link and to the other of said pawls.
 23. A control linkage devicefor expeditiously positioning crank assembly dual pawls for engagementas well as disengagement with the ratchet wheel of a ratchet winch,including, a shaft mounted to the ratchet winch for rotation about afirst axis, means for rotating the shaft about the first axis to firstand second positions for engaging and disengaging the pawls,respectively, a first link rotatably connected at one of its ends to theshaft about a second axis which is eccentric to said shaft, a secondlink pivotably attached by one of its ends to the other end of the firstlink, each of said links having attached to their other ends, springmEans each being connected to one of said pawls for urging the pawlsagainst the ratchet wheel when the shaft is in its first position andaway from the ratchet wheel when the shaft is in its second position.24. The invention of claim 23 and including, cam surface meanspositioned adjacent one of said pawls for guiding said one pawl towardthe wheel when the shaft is in its second position.
 25. The invention ofclaim 23 wherein the spring means is further defined as, a first springconnected to the other end of said first link and to one of said pawls,and a second spring connected to the other end of said second link andto the other of said pawls.